The main objective of the proposed MULTI-MON research project is to develop tools for next-generation multi-modal biodiversity assessment and monitoring of small stagnant freshwater wetlands (SSWs) through the characterization of their underwater ecoacoustic expression and the comprehensive assessment of environmental genetic profiles. Our comparison of conventional biodiversity assessment with non-invasive combined underwater soundscape and eDNA-scape approaches and their synthesis will pave the way for more efficient biodiversity monitoring of SSWs. We are planning a series of carefully designed experimental studies to be conducted in experimental tanks and in three pilot sites. Within the three interlinked work packages of the MULTI-MON project we will: (1) develop new standards for studying aquatic communities and the dynamics of eDNA/eRNA degradation at different time scales; build a regional DNA sequence reference database and develop species-specific eDNA probes for target species; (2) gain information on the complexity and heterogeneity of the soundscape and vibroscape in SSWs, their daily and seasonal dynamics, and build reference sound libraries to identify target species; (3) datasets collected through next-generation biomonitoring will be compared and integrated with conventional approaches for assessing biotic diversity; we will evaluate the effectiveness of these methods for target species detection and use methodologically specific indices of biotic diversity to compare structure and dynamics in aquatic communities.